Just got back with our DD 3.5 and DS 2. They loved epcot, we actually spent almost 2 full days there.
In WS-
Mexico- they loved the ride there (both named this their favorite ride of the trip, I have no idea why!). They also loved looking at the items for sale there. Loved trying on the big hats & trying the Mexican instruments. They have a Kidstop there where they can make masks. I think we spent about 2 hours in this pavilion.
Norway-DD loved Maelstrom, DS was a little scared.
Germany- they loved the big train set they have outside.
They really enjoyed walking around the rest of the world, especially seeing any shows. Loved the fife & drum band in front of the U.S. pavilion. We stayed at the Baordwalk so we did this walk a lot & every time there was something new that they noticed.
On the other side-
HISTA- both hated this and had to leave in the middle of it. This was the only ride or movie in any of the parks that they did not like.
Figment- DS loved it & went on 3 times, DD only once.
Crush- both LOVED this
Living Seas- liked the fish
Living with the Land- both LOVED this. Went on it 3 times.
Spceship Earth-both loved this
Not sure why, but we didn't see any characters in Epcot, maybe our timing was just off, bit the kids didn't seem to notice. Epcot was a lot of fun though.